Gun



W. SUMMERBELL v GUN Filed July 15, 19:59

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Patented Dec. 7, 1943 UNI-TED STATES PATENT OFFICE l GUN WilliamSummerbell, vWatervliet, N. Y. Application July 13, 1939, Serial No.284,255 4 claims. (c1. li27o (Granted under the act of March 3, 1883,as` 1 amended April 30, 1928; 370 0. G. 757) The invention describedherein may be manufactured and used by or for the Goverment forgovernmental purposes, without the payment to me of any royalty thereon.

This invention relates toa gun.

In guns of the type shownin Patent No. 1,144,285 of June 22, 1915, abreech block operating on the blow-back principle is arrested at the endof recoil and then released by a trigger to advance a cartridge into thegun barrel.

'Ihe purpose of this invention is to provide a simple and efficient searand trigger mechanism for a breech block and to provide means foropposing actuation of the trigger to release the block in the event thata cartridge is already in( the barrel. This latter provision isparticularly necessary in a gun using fused ammunition.

The specific nature of the invention as well as other objects andadvantages thereof will clearly appear from a description of a preferredembodiment as shown in the accompanying drawings in which:

Fig. 1 is a plan view of the breech end of a gun with parts removed andparts in section showing the breech block in battery and the trigger innormal position.

Figs. 2 and 3 are sectional views on' the corre- Fig. 4 is a view inside elevation of therear end of the gun frame.

Fig. 5 is a sectional Fig. 1. g

Fig. 6 is a sectional view on the line 6-6 of Fig. 5.

Referring to the drawings by characters of reference there is shown agun frame A, a barrel B xed to the frame, and a reciprocable breechblock C of the blow-back type. The means for checking the breech blockin recoil and returning it to ring position or into battery forms nopart of this invention and is not shown. The breech block is arranged toadvance a round of ammunition D into the chamber b of the barrel and toiire the round before the block reaches the rear face of the barrel sothat the gas pressure is rst utilized to arrest the forward motion ofthe block before acting to drive it rearwardly in recoil. The lower faceof the breech block is formed with a lug 5 having a cam face 6 inclinedto the longitudinal axis of the block and a shoulder 'I disposedtransversely of the axis of the block.

The gun frame A, as shown in Fig. 2 is formed from a. cylindrical tubethat is partially cut away view on the line 5-5 of to receive spacedparallel plates 8--8 for supporting and guiding the breech block. Atrigger housing 9 is attached by means of screws I0 to the under side ofthe lower plate 8 adjacent its rear extremity.

A sear II mounted in thehousing 9 on a pivot pin I2 has a. rearwardlyextending arm I3, a forwardly extending arm I4, and a laterallyextending arm I5. An upright stud I6 on the arm I3 extends throughv anopening I'I in the lower plate 8 and into the path of movement of thelug 5 on the breech block. A depending stud I 8 on the lateral arm I5 isdisposed in the path of movement of the toe I9 of a trigger 26.

The trigger is positioned transversely of the housing.9, underlies therear arm I3 of the sear, and is mounted on a pivot pin 2| threadedlysecured in the housing. The shank of the trigger passes through anopening 22 in a safety bolt 23 which is slidably mounted in the housing.The lingerv piece of the trigger projects laterally from the housing infront o f a rigid handle 24 on the housing. j

A safetir latch 25 slidably mounted in the han'- dle and normally urgedoutwardlyv against a stop shoulder 26 by means of a spring 21 has asolidinner end projecting into the path of movement of the bolt 23. Anaperture 28*V is formed in the latch adjacent the solid inner end sothat when the latch is moved towardsthe gun frame against the action ofthe spring, the aperture will bein 4line with'the bolt 23 to enable thebolt to'be moved rearwardly under impulse from the trigger.

A plunger 29 disposed transversely in the housing 9 is held by a spring30 against the forwardly extending arm I4 of the sear II. The plungernormally maintains the sear in a position with the upright stud I 6 inthe path of the lug 5 of the breech block and with the depending stud I8in rearmost position whereby it acts on the toe I9 of the trigger 20 tohold the projecting finger piece of the trigger in foremost position.Such positioning of the trigger insures the forward displacement of thesafety bolt 23 with the safety latch 25 automatically moved or held in aposition to oppose retraction of the bolt and movement of the trigger.

'Iw'he gun barrel B (Fig. 6) is provided with a counterbored radialpassage 3l for housing a plunger 32 whose inner end is normallyprotruded into the cartridge chamber b by means of a. spring 33 actingon a collar 34. The spring is seated on a plug 35 threaded into thebarrel to close the passage 3| and the plug is provided to an operatingrod 43 pivotally connected to the trigger 20. The slide is formed with adiametral slot 44 for receiving a latch 45 which is mounted adjacent itsforward end on a pivot pin 4G. Ak

rearwardly extending nger 41 on the latch extends nto the slot 39 in thehousing and its rear end is normally positioned forwardly of the plunger32. The latch is maintained in this position by means of a p1unger48 andplunger spring 49 housed in the slide.

The elements of the trigger group, when at rest, are normally in theposition shown in Fig. l. When the breech block C is retracted the camface 6 of the lug 5 strikes the upright stud I6 on the sear and causesthe sear to rotate about its pivot and compress the spring 30. When thelug clears the stud I6,.the sear is immediately restored by spring 3l)to interpose the stud IB in the path of the shoulder 1 and thereby holdthe breech block in the retracted or loading position.

When it is desired to release the breech block so that it may advance acartridge into the barrel, the operator grasps the rigid handle 24 andthe trigger 20, employs his thumb to move the safety latch 25 and alignthe aperture 28 with the safety bolt 23, and then contracts his ngers topull the trigger 20. 'I'he toe I9 of the trigger acts on the dependingstud I8 to move the sear and release the breech block.

Upon retraction of the trigger the slide 40 and latch 45 are also movedrearwardly and the latch is positioned in line with the plunger 32. Asthe carriage advanced by the breech block entersthe chamber b of thebarrel theplunger 32 is moved outwardly-and displaces the latch. Uponrelease of the trigger the slide returns to its normal forward positionand moves the latch clear of the plunger 32 so that therspring pressed`plunger 48-49 may restore it to its normal position. 'Under thecondition where a cartridge isin the chamber and the breech block heldin the loadingposition by the sear, the plunger 32 is extruded into thepath of the latch and will thereby prevent retraction of the triggerwhich would release the breech block to advance a second cartridgetowards the already loaded chamber b. 5 I claim:

1. In a gun, a frame, a breech block reciprocable in the frame, a lug onthe breech block, a housing' attached to the frame,a searpivotallymounted in the housing transversely thereof and .formed with a forwardlyextending arm, a rearwardly extending arm and a laterally extending arm,a stud on the rearward arm extending into the frame for engagement withthe lug on the breech block, a downwardly extending stud on the lateral`arm, a spring acting on the forward arm, a trigger pivotally mountedtransversely in the housing and having a toe engaging the stud on thelateral arm of the sear, a safety bolt in the housing operativelyengaged by the trigger, and a manually operable latch normally opposingmovement of the bolt.

2. The invention of claim 1 characterized in that the relative positionof the trigger latch and trigger is such that they may be manuallyoperated substantially simultaneously with one hand to release thebreech block.

3. In a gun,V a frame, a breech block reciprocable in the frame, ahousing attached to the frame, a sear pivoted in the housing formovement in a plane parallel tothe axis of reciprocation of the breechblock, a stud on the sear extending into the frame in a directiontransverse to the plane of sear movement, a lug on the breech blockadopted to be engaged by the stud,

means normally holding the sear in position to engage the breech block,and. atrigger pivotally mounted in thehousing, in a plane parallel andadjacent to the sear and overlapping the sear and having operativeengagement therewith, to move the sear and be moved thereby.

4. In a gun, a frame, a housing attached to the frame and including aprojecting. handle, a trigger pivotally mounted in the housing forswinging movement toward the handle,Y a safety bolt in the housing andconnected to the trigger for reciprocation in a direction Vtransverse tothe handle upon movement, of the trigger, a, latch mounted in the handlefor sliding'4 movement along the axis thereof and normally opposingmovement of the bolt, and a thumbpiece on the latch for moving the latchto free the bolt.

WILLIAM ,SUMMERBELL

